TIANJIN, Dec. 20 (Xinhua) -- On Dec. 22, the winter solstice, the last beautiful "star-moon fairy tale" of 2023 will be staged on this day, when Jupiter, the largest of the eight planets in the solar system, will be conjunct a waxing gibbous moon. Astronomical science popularization experts said that the public in all parts of China could enjoy this beautiful picture of the "big man" and the "moon girl" on a romantic date and composing a "winter love song" with the naked eye facing the southeast sky that night.
Liu Ning, a Beijing starry sky photography enthusiast, photographed Jupiter's conjunction with the Moon in Mentougou in Beijing on February 18, 2013. (Photo courtesy of me).
"Combination" is a term in astronomy that describes the relative position of celestial bodies. A "conjunction" occurs when two celestial bodies have the same right ascension or ecliptic longitude (the coordinate value of celestial bodies such as the sun, moon, and planets on the celestial sphere) in the sky.
Xiu Lipeng, a member of the Chinese Astronomical Society and an expert in astronomical science popularization, said that the eight planets in the solar system will have a moon conjunction phenomenon about once a month. In addition to the conjunction of Venus and the Moon, the conjunction of the Jupiter Moon is also very good.
A close-up of Jupiter taken by Beijing star photography enthusiast Pu Shi in Yuyuantan Park in Haidian, Beijing, September 1, 2022. (Photo courtesy of me).
As the fastest rotating planet in the solar system, Jupiter is not only one of the most visible objects to the naked eye, but also loved by stargazers for its colorful striped cloud bands.
The period of the Moon's movement on the background of the celestial sphere is about a lunar month, while Jupiter is about 12 years, so the Moon will "catch" Jupiter once every month, and even twice in some months. From the Earth, Jupiter observes about half a year for about half a year, and can meet Jupiter conjunct the Moon about 5 to 7 times, but due to factors such as the moon phase and the position of the sun, it is not suitable for observation every time.
This is a view of Jupiter's conjunction with the Moon taken on October 12, 2018 at the Ming Palace Ruins Park in Nanjing, Jiangsu. Xinhua News Agency (photo by Su Yang).
What is so special about this Jupiter conjunction on the 22nd?Xiu Lipeng introduced, Jupiter's brightness is -2The 7th is very conspicuous in the night sky, and even if the moon phase on the night of the 22nd is full gibbous, close to the full moon, and the moonlight is dazzling, Jupiter is "not to be outdone" to compete with it.
Specifically, after sunset that day, the bright Jupiter and a full gibbous moon are already hanging high in the southeastern sky, which is very beautiful to see at close range. Over time, around 20 o'clock, the two are "closest" to each other, only about 2 degrees, about 4 full moons apparently in diameter;When the 22 o'clock meets, the distance between the two is still not far;After the wee hours of the morning, both will fall below the horizon.
This is the conjunction of Saturn (top right) and Jupiter (bottom right) with the Moon taken at Tsinghua University on December 17, 2020. (Photo courtesy of Tsinghua Astronomical Association).
Jupiter is like a diamond, sparkling brightly. Since there are no other celestial bodies that are too bright around, this beautiful scenery accompanied by the stars and the moon is extremely clear, and the viewing effect is very good, and the public who like the 'fairy tale of the stars and the moon' should not miss it. Xiu Lipeng said.